Fluidpressure communication passages in a multiple radialchamber fluidhandling device

ABSTRACT

The stator of a fluidhandling device has inner control faces forming clearances with end faces of a rotor. The fluid pressures in clearances at opposite ends of the rotor, which has two axially spaced groups of angularly spaced working chambers for radial pistons, are equalized by communication passages connecting each working chamber near one clearance with the respective other clearance.

United States Patent Eickmann [4 1 Aug. 15, 1972 FLUIDPRESSURE COMMUNICATION 2,895,426 7/1959 Orshansky ..91/485 PASSAGES IN A MULTIPLE 3,086,477 4/1963 Ruhl ..9l/487 RADIALCHAMBER FLUIDHANDLING 3, l 55,047 1 H1964 Keel ..9 1/485 DEVICE Appl. No.: 888,231

Foreign Application Priority Data 7 Primary Examiner-Carlton R. Croyle Assistant Examiner-John J. Vrablik Attorney-Michael S. Striker [57] ABSTRACT The stator of a fluidhandling device has inner control faces forming clearances with end faces of a rotor. The fluid pressures in clearances at opposite ends of the rotor, which has two axially spaced groups of an- Dec 27 1968 Austria ..l2648/68 *gulafly Spaced chambers radial Pistons, are equalized by communication passages connecting u.s. Cl ..91/486, 91/492 each WPYkiIIg Chamber near (me clearance with the Int. Cl ..F0lb 1/06, FOlb 3/00, FOlb 13/06 respectwe other clearance Field of Search ..9l/484487, 489, 91/492; 417/273 References Cited 10 Claims, 2 Drawing Figures UNITED STATES PATENTS 2,620,736 12/1952 Overbeke ..9l/485 l H E 8 n /0 /9 1 77 78 10 H PM 1: 2/ l/ 27 20 Zita; :1? w

l l l l3 7 l2 5 7 l4 INVENTOR:

BY KARL. E/CKMANA/ JLLQQJKM FLUIDPRESSURE COMMUNICATION PASSAGES IN A MULTIPLE RADIALCHAMBER FLUIDHANDLING DEVICE It is known, that fluidhandling devices, like. pumps, motors, compressors, engines, transmissions which have a plurality of axially spaced fluidhandling working chamber groups or sets with working chambers of radially expanding and contracting volume and clearances on both ends of a fluidhandling body or cylinder block of the fluidhandling body between controlfaces of end covers of the housing are operating successfully, if the pressure in both or all working chamber groups and controlclearances is about equal. That is explained for example in my US. Pat. No. 3,398,698.

It has now been found, however, that, if the pressure in one of the working chamber groups is higher than in the other working chamber group, the pressure is also considerably higher in one of the clearances, than in the other. The fluidhandling body or cylinder block of the device, which contains the working chambers of the several working chamber groups and which is preferably arranged as a revolving rotor, is then forced by the higher fluidpressure in one of the controlclearances on one end of the body into move in the opposite direction, which results in higher friction at one of the controlclearances and in higher leakage of fluid in the other clearances of the device. At extremely different pressures in the controlclearances this causes to wearing off or fusing of the controlfaces of one of the controlclearances'and thereby disturbances.

It is the main object of this invention to prevent those difficulties by providing a fluidhandling body in a fluid handling device, which can operate reliably also at very different pressures in different working chamber groups of the fluidhandling device.

The object of the invention is obtained by communication passages which extend from a working chamber at one in through the cylinder body into the clearance on the opposite end of the body and having balancing ports at the other endface of the body.

It is therefore another object of the invention to provide a communication passage from one fluidhandling working chamber through the fluidhandling body or rotor and through its opposite endface into the clearance on the opposite end of the fluidhandling body for equalizing the fluidpressure in the respective connected portions of the two clearances between.

A further object of the invention is to provide communication passages from each working chamber of each working chamber group through a respective portion of the body and through the respective opposite endface of the body.

According to another object of the invention the communication passages are extended through the respective portion of the body between working chambers of another workingchamber group and beyond the other working chamber group.

Another object of the invention is to port each communication passage at a location radially and angularly distanced from the fluidhandling passages of the working chambers.

CROSS REFERENCE TO RELATED PATENTS The term fluidhandling device refers, for example, to radial piston machines, vane-type fluidhandling devices or gearor trochoid-type fluidhandling devices as disclosed for example in -my US. Pat. Nos.

3.320,897 3.223.046 3.398.698 3.416.460 and others.

BRIEF DESCRIPTION OF THE DRAWING A cylinder block, or fluidhandling body, preferable a rotor l is located in the housing 12 of the fluidhandling device. It could, however, also be a stator, depending on the operation of the device. Rotor l is rotatably supported in bearings 10 in covers 13 and 14 for bearing the shaft 9 which in turn bears rotor l for rotation about its axis. Connecting means: 11 may be provided for enabling an axial movement between the shaft 9 and rotor 1. Rotor l is provided with working chambers 2 and 3 which are associated in two axially spaced working chambergroups of the rotor and which extend substantially in radial direction. Fluidhandling passage means 27 and 28 extend from the respective working chambers 2 or 3 through a portion of rotor l and through the end face on the adjacent end of the rotor l for passing fluid into or out of the respective working chamber 2 or 3. Displacement means 4, shown to be radially movable pistons, are provided in the respective working chambers for substantially radially enlarging and contracting the volume of the respectively associated working chamber 2 or 3. Displacement members 5 maybe associated with the displacement means 4 and cooperate with an actuator or reacting ring 6 supported by supports 7 and home in bearings 8 for revolving around an axis excentric to that of rotor 1. The actuator means 6 thereby actuates the displacement stroke of displacement means 4, 5 for the periodic expansion and contraction of the volumes of the working chambers 2 and 3. Stationary inner control faces 19 and 20 are provided on the covers 13 and 14. The ends of rotor l are provided also with endfaces 22 and 23. The rotor l with end faces 22, 23 is fitted between the stationary controlfaces l9 and 20 for sealing thereagainst and for revolving closely along them. Between the stationary controlfaces 19 and 20 and'the rotary controlfaces 22 and 23 are clearances with thin films of fluid for prevention of sticking between the faces. Thus,.at one end of the rotor I is the clearance 25 located and on the other end is the clearance 26 located. Faces 19 and 22 form the: clearance 25. Faces 20 and 23 form the clearance 26. In the rear of, and in front of shaft 9 are the entrance ports and exit ports provided in each cover 13 and 14, but they are not visible in the drawing because the section does not cross through the entrance and exit ports. From each working chamber 2 extends a fluidpassage 28 through the respective rotorportion and through the rotary end face .22 into the clearance 25 for periodically communicating with the entrance and exit ports in cover 13 for taking fluid into the chambers 2 and for expelling fluid out of chambers 2. From each fluidhandling working camber 3 extends a fluidpassage 27 through the respective portionof rotor l and through the adjacent rotary end face 23 into the clearance 26 for periodically communicating with the entrance and exit ports in cover 14 and thereby to supply fluid into the expanding working chambers 3 and to expell fluid out of the contracting working chambers 3. The arrangement of the device as heretofore described is in partly known from my US. Pat. No. 3,398,698.

It has now been discovered, that, if the pressure in fluid in the several working chambers of working chamber group 3 is substantially higher than in working chambers 2, the pressure in clearance 26 is also higher than in clearance 25. That forced rotor 1 into too close sliding along stationary controlface 19, so that controlfaces 19 and 22 fuse. On the other hand, if pressure in several working chambers 2 was substantially higher than the pressure in some working chambers 3, the pressure in clearance 25 became higher than in clearance 26 and the rotor I became pressed toward controlface 20 for too close sliding of controlface 23 along controlface 20. That resulted in sticking and fusing between controlfaces 20 and 23 and in disturbance of the clearance 26 and thereby in disturbing the whole device. The troubles occured especially, if two different flows of fluid passed through the device. In such cases, one flow of fluid passes through working chamber group 2 and the other through working chamber group 3. It often happens, that due to different loads on the different flows the pressure in them becomes different. The damage to the device happened then very suddenly. Even the utilization of suitable controlface materials did not work at high pressure differential in the different flows of fluid. In accordance with the invention, a communication passage 17 extends from the respective working chamber 3 through a respective portion of the rotor l and through the rotary end face 22 on the opposite end of the body 1 into the clearance 25 for communicating with the same. Communication passage 18 extends through the opposite rotor portion beyond the other working chamber group 2. The communication passages 17, 18 are different from the known fluidpassages 27 and 28. They may extend parallel to them. But it is preferred, that the communication passages 17, 18 are located radially outward of the fluidhandling passages 27 and 28 respectively and that the balancingports 30, 31 of the com munication passages are radially and circurnferentially distanced from the control port, fluidhandling passages 27, 28 at the opposite end face. From each working chamber 2 extends a communication passage 18 through a respective rotorportion and beyond the other working chambergroup 3 and through the rotary end face 23 on the opposite end of rotor 1 into the clearance 26 for communicating with the same. Communication passages 17 and 18 are similar in function, but they are oppositely directed and associated with opposite working chamber groups and clearances. It is preferred to provide larger balancing ports 31 and 30 on the ends of the communication passages 17 and 18. They should be correctly located and dimensioned in crossection, because according to the invention it is necessary that the total of pressure in the clearances 25 and 26 on both rotorends must be equalized by the communication passages 17, 18 and balancing ports 30 and 31. Particularly, the port of passage 27 must be balanced by port 31, and passage port 28 must be balanced by port 30. Exactly speaking, not only the crossections of the ports27, 28, 30 and 31 are to be balanced, but also the adjacent clearance portions. Considering this fact, the crossections through the ports 27, 28, 30 and 31 are not exactly equal. Exactly equal are the crossections of the fiuidpressure areas in the clearances 25 and 26. This clearance design is often to be found empirically, for example also by providing pockets 29 or 32, because not only hydrostatic pressures act in the clearances, but also hydrodynamic pressures and thermic influences. If however, the dimensions and locations of the passages and ports of this invention are correct, a reliable and useful operation of the device is assured. In principle, a high pressure balancing port 31 is associated to a high pressure passage port 27 a high pressure balancing port 30 is associated to a high pressure passage port 28 and respective associations are made, if lower pressures are in the respective ports. It is necessary to take care, that the passages 17 and 18 and the ports 30 and 31 do not communicate with the inlet and outlet ports, (not shown) with which the passages 27 and 28 periodically communicate. Because otherwise the device cannot work and would not obtain the desired equalization of pressure fields in the clearances 25 and 26. It is therefore neccessary to space the passages 17 and 18 radially from the passages 27 and 28. It is suitable to extend the communication passages 17 and 18 through the material of the rotor 1 between the chambers of the opposite chamber group and beyond the opposite group. Thereby is a most compact fluidhandling device assured, which is inexpensive in cost and reliable in operation. Passages 16 are discharge passages for guiding leakage fluid away from the central space inside of the respective annular clearance.

The invention is described by way of one embodiment illustrated in the accompanying drawing. The invention, however, shall not be limited to the embodiment described. It is possible to alter the embodiment and the application of the invention within the scope of the invention. The patent shall therefor be only limited by the following claims.

What is claimed, is:

1. Fluid handling device comprising, in combination, housing means having an axis and first and second end covers having first and second confronting control faces extending transversely to said main axis, each of said end covers having inlet and outlet ports of he respective control face; an actuator ring mounted in said housing means eccentric to said axis; a cylinder block mounted in said housing means coaxial with said axis and having opposite first and second end faces cooperating with said first and second control faces, respectively, and forming first and second clearances with the same, said cylinder block being formed with first and second axially spaced first and second sets of circurnferentially spaced radial working chambers located adjacent said first and second end faces, respectively, and including first and second fluid displacement means located in said working chambers of said first and second sets of working chambers for radia1 movement and having outer ends slidingly engaging said eccentric actuator ring so that said first and second working chambers expand and contract, said cylinder block having first and second fluid handling passages connecting said first and second sets of working chambers with said first and second outer end faces, respectively, and forming first and second sets of control ports on the same cooperating with said inlet and outlet ports of said first and second control faces, respectively, and being radially equidistant from said main axis, said cylinder block further having first and second communication passages connecting said first and second sets of working chambers with said second and first outer end faces, respectively, forming second and first balancing recesses on the same, respectively, radially equidistant from said main axis, each communication passage extending from a working chamber of one of said sets of working chambers through the portion of said cylinder block which contains the respective other set of working chambers to the end face adjacent said other set of working chambers, and forming therein a balancing recess so that pressure fluid flowing from the working chambers adjacent any one of said clearances through the respective communication passages to the respective other clearance balances the pressure of the fluid in said one clearance whereby said cylinder block is axially balanced.

2. Fluid handling device as claimed in claim 1 wherein said working chambers of said first and second sets of working chambers are angularly staggered relative to each other in circumferential direction; and wherein each communication passage of said first set of communication passages passes between two working chambers of said second set of working chambers, and each communication passage of said second set of communication passages passes between two working chambers of said first set of working chambers.

3. Fluid handling device as claimed in claim 1 wherein said communication passages are parallel to said axis.

4. Fluid handling device as claimed in claim 1 wherein said fluid handling passages communicate with the inner ends of said working chambers; and wherein said communication passages communicate with said working chambers radially outward of said fluid handling passages.

S. Fluid handling device as claimed in claim 1 wherein said balancing recesses have a greater flow cross section than the respective communication passages.

6. Fluid handling device as claimed in claim 1 wherein said fluid handling passages have greater flow cross sections than said communication passages.

7. Fluid handling device as claimed in claim I wherein said working chambers of said first and second sets of working chambers are equidistant from said axis; and wherein said fluid handling passages are parallel to said axis and equidistant from the same; whereas said working chambers of said first and second sets of working chambers are angularly staggered relative to each other in circumferential direction; wherein each communication'passage of said first set of communication passages passes between two working chambers of said second set of working chambers, and each communication passage of said second set of communication passages passes between two working chambers of said first set of working chambers; and wherein said communication passages are parallel to said axis and equidistant from the same.

8. Fluid handling device as claimed in claim 1 including a drive shaft having said axis and connected with 'd I de bl kfor tt' n. i id har? ling 52388 as claimed in claim 1 wherein said first and second sets of balancing recesses are radially spaced from said first and second sets of control ports, respectively, on said first and second end faces, respectively.

10. Fluid handling device as claimed in claim 9 wherein said first and second sets of balancing recesses are angularly staggered in circumferential direction relative said first and second sets of control ports, respectively, on said first and second end faces, respec tively. 

1. Fluid handling device comprising, in combination, housing means having an axis and first and second end covers having first and second confronting control faces extending transversely to said main axis, each of said end covers having inlet and outlet ports of he respective control face; an actuator ring mounted in said housing means eccentric to said axis; a cylinder block mounted in said housing means coaxial with said axis and having opposite first and second end faces cooperating with said first and second control faces, respectively, and forming first and second clearances with the same, said cylinder block being formed with first and second axially spaced first and second sets of circumferentially spaced radial working chambers located adjacent said first and second end faces, respectively, and including first and second fluid displacement means located in said working chambers of said first and second sets of working chambers for radial movement and having outer ends slidingly engaging said eccentric actuator ring so that said first and second working chambers expand and contract, said cylinder block having first and second fluid handling passages connecting said first and second sets of working chambers with said first and second outer end faces, respectively, and forming first and second sets of control ports on the same cooperating with said inlet and outlet ports of said first and second control faces, respectively, and being radially equidistant from said main axis, said cylinder block further having first and second communication passages connecting said first and second sets of working chambers with said second and first outer end faces, respectively, forming second and first balancing recesses on the same, respectively, radially equidistant from said main axis, each communication passage extending from a working chamber of one of said sets of working chambers through the portion of said cylinder block which contains the respective other set of working chambers to the end face adjacent said other set of working chambers, and forming therein a balancing recess so that pressure fluid flowing from the working chambers adjacent any one of said clearances through the respective communication passages to the respective other clearance balances the pressure of the fluid in said one clearance whereby said cylinder block is axially balanced.
 2. Fluid handling device as claimed in claim 1 wherein said working chambers of said first and second sets of working chambers are angularly staggered relative to each other in circumferential direction; and wherein each communication passage of said first set of communication passages passes between two working chambers of said second set of working chambers, and each communication passage of said second set of communication passages passes between two working chambers of said first set of working chambers.
 3. Fluid handling device as claimed in claim 1 wherein said communication passages are parallel to said axis.
 4. Fluid handling device as claimed in claim 1 wherein said fluid hAndling passages communicate with the inner ends of said working chambers; and wherein said communication passages communicate with said working chambers radially outward of said fluid handling passages.
 5. Fluid handling device as claimed in claim 1 wherein said balancing recesses have a greater flow cross section than the respective communication passages.
 6. Fluid handling device as claimed in claim 1 wherein said fluid handling passages have greater flow cross sections than said communication passages.
 7. Fluid handling device as claimed in claim 1 wherein said working chambers of said first and second sets of working chambers are equidistant from said axis; and wherein said fluid handling passages are parallel to said axis and equidistant from the same; whereas said working chambers of said first and second sets of working chambers are angularly staggered relative to each other in circumferential direction; wherein each communication passage of said first set of communication passages passes between two working chambers of said second set of working chambers, and each communication passage of said second set of communication passages passes between two working chambers of said first set of working chambers; and wherein said communication passages are parallel to said axis and equidistant from the same.
 8. Fluid handling device as claimed in claim 1 including a drive shaft having said axis and connected with said cylinder block for rotation.
 9. Fluid handling device as claimed in claim 1 wherein said first and second sets of balancing recesses are radially spaced from said first and second sets of control ports, respectively, on said first and second end faces, respectively.
 10. Fluid handling device as claimed in claim 9 wherein said first and second sets of balancing recesses are angularly staggered in circumferential direction relative said first and second sets of control ports, respectively, on said first and second end faces, respectively. 